/*!

\if MANPAGES
\page echoscu DICOM verification (C-ECHO) SCU
\else
\page echoscu echoscu: DICOM verification (C-ECHO) SCU
\endif

\section echoscu_synopsis SYNOPSIS

\verbatim
echoscu [options] peer port
\endverbatim

\section echoscu_description DESCRIPTION

The \b echoscu application implements a Service Class User (SCU) for the
Verification SOP Class.  It sends a DICOM C-ECHO message to a Service Class
Provider (SCP) and waits for a response.  The application can be used to verify
basic DICOM connectivity.

\section echoscu_parameters PARAMETERS

\verbatim
peer  hostname of DICOM peer

port  tcp/ip port number of peer
\endverbatim

\section echoscu_options OPTIONS

\subsection echoscu_general_options general options
\verbatim
  -h    --help
          print this help text and exit

        --version
          print version information and exit

        --arguments
          print expanded command line arguments

  -q    --quiet
          quiet mode, print no warnings and errors

  -v    --verbose
          verbose mode, print processing details

  -d    --debug
          debug mode, print debug information

  -ll   --log-level  [l]evel: string constant
          (fatal, error, warn, info, debug, trace)
          use level l for the logger

  -lc   --log-config  [f]ilename: string
          use config file f for the logger
\endverbatim

\subsection echoscu_network_options network options
\verbatim
application entity titles:

  -aet  --aetitle  [a]etitle: string
          set my calling AE title (default: ECHOSCU)

  -aec  --call  [a]etitle: string
          set called AE title of peer (default: ANY-SCP)

association negotiation debugging:

  -pts  --propose-ts  [n]umber: integer (1..38)
          propose n transfer syntaxes

  -ppc  --propose-pc  [n]umber: integer (1..128)
          propose n presentation contexts

other network options:

  -to   --timeout  [s]econds: integer (default: unlimited)
          timeout for connection requests

  -ta   --acse-timeout  [s]econds: integer (default: 30)
          timeout for ACSE messages

  -td   --dimse-timeout  [s]econds: integer (default: unlimited)
          timeout for DIMSE messages

  -pdu  --max-pdu  [n]umber of bytes: integer (4096..131072)
          set max receive pdu to n bytes (default: 16384)

        --repeat  [n]umber: integer
          repeat n times

        --abort
          abort association instead of releasing it
\endverbatim

\subsection echoscu_tls_options transport layer security (TLS) options
\verbatim
transport protocol stack:

  -tls  --disable-tls
          use normal TCP/IP connection (default)

  +tls  --enable-tls  [p]rivate key file, [c]ertificate file: string
          use authenticated secure TLS connection

  +tla  --anonymous-tls
          use secure TLS connection without certificate

private key password (only with --enable-tls):

  +ps   --std-passwd
          prompt user to type password on stdin (default)

  +pw   --use-passwd  [p]assword: string
          use specified password

  -pw   --null-passwd
          use empty string as password

key and certificate file format:

  -pem  --pem-keys
          read keys and certificates as PEM file (default)

  -der  --der-keys
          read keys and certificates as DER file

certification authority:

  +cf   --add-cert-file  [c]ertificate filename: string
          add certificate file to list of certificates

  +cd   --add-cert-dir  [c]ertificate directory: string
          add certificates in d to list of certificates

ciphersuite:

  +cs   --cipher  [c]iphersuite name: string
          add ciphersuite to list of negotiated suites

  +dp   --dhparam  [f]ilename: string
          read DH parameters for DH/DSS ciphersuites

pseudo random generator:

  +rs   --seed  [f]ilename: string
          seed random generator with contents of f

  +ws   --write-seed
          write back modified seed (only with --seed)

  +wf   --write-seed-file  [f]ilename: string (only with --seed)
          write modified seed to file f

peer authentication:

  -rc   --require-peer-cert
          verify peer certificate, fail if absent (default)

  -vc   --verify-peer-cert
          verify peer certificate if present

  -ic   --ignore-peer-cert
          don't verify peer certificate
\endverbatim

\section echoscu_notes NOTES

\subsection echoscu_dicom_conformance DICOM Conformance

The \b echoscu application supports the following SOP Classes as an SCU:

\verbatim
VerificationSOPClass                1.2.840.10008.1.1
\endverbatim

Unless the \e --propose-ts option is used, the echoscu application will only
propose the transfer syntax

\verbatim
LittleEndianImplicitTransferSyntax  1.2.840.10008.1.2
\endverbatim

\section echoscu_logging LOGGING

The level of logging output of the various command line tools and underlying
libraries can be specified by the user.  By default, only errors and warnings
are written to the standard error stream.  Using option \e --verbose also
informational messages like processing details are reported.  Option
\e --debug can be used to get more details on the internal activity, e.g. for
debugging purposes.  Other logging levels can be selected using option
\e --log-level.  In \e --quiet mode only fatal errors are reported.  In such
very severe error events, the application will usually terminate.  For more
details on the different logging levels, see documentation of module "oflog".

In case the logging output should be written to file (optionally with logfile
rotation), to syslog (Unix) or the event log (Windows) option \e --log-config
can be used.  This configuration file also allows for directing only certain
messages to a particular output stream and for filtering certain messages
based on the module or application where they are generated.  An example
configuration file is provided in <em>\<etcdir\>/logger.cfg</em>.

\section echoscu_command_line COMMAND LINE

All command line tools use the following notation for parameters: square
brackets enclose optional values (0-1), three trailing dots indicate that
multiple values are allowed (1-n), a combination of both means 0 to n values.

Command line options are distinguished from parameters by a leading '+' or '-'
sign, respectively.  Usually, order and position of command line options are
arbitrary (i.e. they can appear anywhere).  However, if options are mutually
exclusive the rightmost appearance is used.  This behavior conforms to the
standard evaluation rules of common Unix shells.

In addition, one or more command files can be specified using an '@' sign as a
prefix to the filename (e.g. <em>\@command.txt</em>).  Such a command argument
is replaced by the content of the corresponding text file (multiple
whitespaces are treated as a single separator unless they appear between two
quotation marks) prior to any further evaluation.  Please note that a command
file cannot contain another command file.  This simple but effective approach
allows one to summarize common combinations of options/parameters and avoids
longish and confusing command lines (an example is provided in file
<em>\<datadir\>/dumppat.txt</em>).

\section echoscu_environment ENVIRONMENT

The \b echoscu utility will attempt to load DICOM data dictionaries specified
in the \e DCMDICTPATH environment variable.  By default, i.e. if the
\e DCMDICTPATH environment variable is not set, the file
<em>\<datadir\>/dicom.dic</em> will be loaded unless the dictionary is built
into the application (default for Windows).

The default behavior should be preferred and the \e DCMDICTPATH environment
variable only used when alternative data dictionaries are required.  The
\e DCMDICTPATH environment variable has the same format as the Unix shell
\e PATH variable in that a colon (":") separates entries.  On Windows systems,
a semicolon (";") is used as a separator.  The data dictionary code will
attempt to load each file specified in the \e DCMDICTPATH environment variable.
It is an error if no data dictionary can be loaded.

\section echoscu_copyright COPYRIGHT

Copyright (C) 1994-2017 by OFFIS e.V., Escherweg 2, 26121 Oldenburg, Germany.

*/
